Co-pending UK patent applications 0207020.9, 0206994.6, 0206987.0 and 0206995.3 disclose a system and apparatus for generating audio and/or video (a/v) productions. The system may according to one application utilize a camera with a camera utility device and a personal digital assistant (PDA). The camera utility device and the digital assistant are provided with a wireless communications link. The camera is arranged in use to generate a/v material by capturing images and sounds which are recorded on a recording medium such as, for example, a cassette tape. The utility device generates metadata describing the content of the a/v material and/or other attributes of the a/v material such as camera parameter settings used to generate the a/v material.
The metadata may be arranged in the form of a hierarchical data structure including a volume identifier at a first level, and shot or sub-shot identifier at a second level. The volume identifier provides an indication of the data carrier on which the a/v material is stored. The shot or sub-shot identifiers provide an indication of the location of shots or sub-shots of a/v material on the data carrier. Metadata describing the content or attributes of the shots may, for example, be stored in association with the shot or sub-shot identifier in correspondence with the shot or sub-shot of a/v material to which the metadata relates.
Generally, for a system generating metadata describing the content or the attributes of a/v material, it is desirable to efficiently identify the location of the a/v material on a data carrier on which the material is stored, with respect to which the metadata has been generated.